Journal of Geophysical Research: Space Physics最新文献

{"title":"Solar Semidiurnal Variations in the Thermosphere and Ionosphere Forced From Above and From Below","authors":"Jeffrey M. Forbes, Xiaoli Zhang, Chihoko Cullens, Astrid Maute","doi":"10.1029/2024JA033353","DOIUrl":"https://doi.org/10.1029/2024JA033353","url":null,"abstract":"<p>The nature and origins of solar-synchronous semidiurnal variations (SW2) in the thermosphere and ionosphere are explored through analysis of Thermosphere Ionosphere Electrodynamics General Circulation Model (TIEGCM) simulations that include and exclude forcing by tides at its 97-km lower boundary derived from Ionospheric Connection (ICON) explorer data. SW2 consists of two components, one excited in-situ (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mrow>\u0000 <mtext>SW</mtext>\u0000 <mn>2</mn>\u0000 </mrow>\u0000 <mi>i</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${text{SW}2}_{i}$</annotation>\u0000 </semantics></math>) and one due to vertical propagation from below the thermosphere (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mrow>\u0000 <mtext>SW</mtext>\u0000 <mn>2</mn>\u0000 </mrow>\u0000 <mi>b</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${text{SW}2}_{b}$</annotation>\u0000 </semantics></math>). <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mrow>\u0000 <mtext>SW</mtext>\u0000 <mn>2</mn>\u0000 </mrow>\u0000 <mi>i</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${text{SW}2}_{i}$</annotation>\u0000 </semantics></math> in turn consists of a part forced by heating due to absorption of solar radiation (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mrow>\u0000 <mtext>SW</mtext>\u0000 <mn>2</mn>\u0000 </mrow>\u0000 <mrow>\u0000 <mi>i</mi>\u0000 <mi>s</mi>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${text{SW}2}_{is}$</annotation>\u0000 </semantics></math>) and a part of “geomagnetic” origin (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mrow>\u0000 <mtext>SW</mtext>\u0000 <mn>2</mn>\u0000 </mrow>\u0000 <mrow>\u0000 <mi>i</mi>\u0000 <mi>g</mi>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${text{SW}2}_{ig}$</annotation>\u0000 </semantics></math>) arising from magnetosphe","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JA033353","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143111448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Durable Electron Density Profile Near the Inner Edge of the Io Torus","authors":"W. S. Kurth, G. B. Hospodarsky, J. B. Faden, J. D. Menietti, A. H. Sulaiman, S. S. Elliott, F. Bagenal, E. G. Nerney, J. E. P. Connerney, F. Allegrini, S. J. Bolton","doi":"10.1029/2024JA033453","DOIUrl":"https://doi.org/10.1029/2024JA033453","url":null,"abstract":"<p>The Juno Waves instrument can be used to accurately determine the electron density inside Io's orbit, the inner Io torus. These observations have revealed a local peak in the electron density just inside <i>M</i> = 5 and at centrifugal latitudes above about 10<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>°</mo>\u0000 </mrow>\u0000 <annotation> ${}^{circ}$</annotation>\u0000 </semantics></math> that is likely the ’cold torus' as identified in Earth-based observations of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msup>\u0000 <mi>S</mi>\u0000 <mo>+</mo>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> ${mathrm{S}}^{+}$</annotation>\u0000 </semantics></math> emissions. This peak or “finger” is separated from the more dense Io torus by a local minimum or ’trough’ at <i>M</i> <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>≥</mo>\u0000 </mrow>\u0000 <annotation> ${ge} $</annotation>\u0000 </semantics></math> 5. The electron densities are inferred by identifying characteristic frequencies of the plasma such as the low-frequency cutoff of <i>Z</i>-mode radiation at <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>f</mi>\u0000 <mrow>\u0000 <mi>L</mi>\u0000 <mo>=</mo>\u0000 <mn>0</mn>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${f}_{L=0}$</annotation>\u0000 </semantics></math> and the low-frequency cutoff of ordinary mode radiation at <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>f</mi>\u0000 <mrow>\u0000 <mi>p</mi>\u0000 <mi>e</mi>\u0000 </mrow>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${f}_{pe}$</annotation>\u0000 </semantics></math> that depend on the electron density. The “finger” density ranges from about 0.2 to 65 <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msup>\u0000 <mtext>cm</mtext>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>3</mn>\u0000 </mrow>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> ${text{cm}}^{-3}$</annotation>\u0000 </semantics></math> and decreases with increasing centrifugal latitude. The “trough” densities range from 0.05 to <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 ","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JA033453","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143111472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resonant Scattering of Sub-keV Electrons by Beam-Driven Electron Cyclotron Harmonic Waves","authors":"Xu Zhang, Anton Artemyev, Vassilis Angelopoulos, Xiao-Jia Zhang, Qianli Ma, Xin An, Ying-dong Jia","doi":"10.1029/2024JA033118","DOIUrl":"https://doi.org/10.1029/2024JA033118","url":null,"abstract":"<p>Electron cyclotron harmonic waves (ECH) play a key role in scattering and precipitation of plasma sheet electrons. Previous analysis on the resonant interaction between ECH waves and electrons assumed that these waves are generated by a loss cone distribution and propagate nearly perpendicular <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>(</mo>\u0000 <mrow>\u0000 <mo>∼</mo>\u0000 <mn>88</mn>\u0000 <mo>°</mo>\u0000 </mrow>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 <annotation> $(sim 88{}^{circ})$</annotation>\u0000 </semantics></math> to the background magnetic field. Recent spacecraft observations, however, have demonstrated that such waves can also be generated by low energy electron beams and propagate at moderately oblique angles <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>(</mo>\u0000 <mrow>\u0000 <mo>∼</mo>\u0000 <mn>70</mn>\u0000 <mo>°</mo>\u0000 </mrow>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 <annotation> $(sim 70{}^{circ})$</annotation>\u0000 </semantics></math>. To quantify the effects of this newly observed ECH wave mode on electron dynamics in Earth's magnetosphere, we use quasi-linear theory to calculate the associated electron pitch angle diffusion coefficient. Utilizing THEMIS spacecraft measurements, we analyze in detail a few representative events of beam-driven ECH waves in the plasma sheet and the outer radiation belt. Based on the observed wave properties and the hot plasma dispersion relation of these waves, we calculate their bounce-averaged pitch angle, momentum and mixed diffusion coefficients. We find that these waves most efficiently scatter low-energy electrons (10–500 eV) toward larger pitch angles, on time scales of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>1</mn>\u0000 <msup>\u0000 <mn>0</mn>\u0000 <mn>2</mn>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> $1{0}^{2}$</annotation>\u0000 </semantics></math> to <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>1</mn>\u0000 <msup>\u0000 <mn>0</mn>\u0000 <mn>3</mn>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> $1{0}^{3}$</annotation>\u0000 </semantics></math> seconds. In contrast, loss-cone-driven ECH waves most efficiently scatter higher-energy electrons (500 eV–5 keV) toward lower pitch-angles. Importantly, beam-driven ECH waves can effectively scatter ionospheric electron outflows out of the loss cone near the magnetic equator. As a result, these outflows become trapped in the magnetosphere, forming a near-field-aligned anisotropic electron populat","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143111358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Investigation Into Far-Flank Magnetic Reconnection at Earth's Magnetopause","authors":"K. M. Sullivan,&nbsp;S. A. Fuselier,&nbsp;K. J. Trattner,&nbsp;S. M. Petrinec,&nbsp;J. L. Burch,&nbsp;D. J. Gershman","doi":"10.1029/2024JA032663","DOIUrl":"https://doi.org/10.1029/2024JA032663","url":null,"abstract":"<p>Magnetospheric Multiscale (MMS) observations have revealed that reconnection occurs along the flanks of Earth's magnetopause, near and past the terminator when the interplanetary magnetic field is southward. However, the question remains how common this reconnection is. Previous research has indicated that reconnection may be suppressed in the far-flank regions due to the high velocity shear between the plasma in the magnetosheath and the plasma in the magnetosphere. This study investigates far-flank reconnection by looking for evidence of reconnection in crossings of the far-flank magnetopause. Forty-one magnetopause crossing events were found that satisfied certain criteria and 35 of these events showed identifiable signs of reconnection. Based on these findings, reconnection is not suppressed along the magnetospheric flanks due to the velocity shear during southward IMF.</p>","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143111446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics of Sporadic E Layer Occurrence in a Global Chemistry-Climate Model: A Comparison With COSMIC-Derived Data","authors":"Tasha Aylett,&nbsp;Wuhu Feng,&nbsp;Daniel R. Marsh,&nbsp;David R. Themens,&nbsp;John M. C. Plane","doi":"10.1029/2024JA033044","DOIUrl":"https://doi.org/10.1029/2024JA033044","url":null,"abstract":"<p>This study presents an analysis of sporadic-E (Es) structures within WACCM-X (the Whole Atmosphere Community Climate Model with thermosphere and ionosphere eXtension), including electrodynamical transport of metallic ions. A set of selection criteria have been developed to identify Es layers in WACCM-X output based on the total metal ion density in each model grid box. These criteria are used to create a climatology of Es, which is compared to Es occurrence rates derived from FORMOSAT/COSMIC-1 (Constellation Observing System for Meteorology, Ionosphere, and Climate) radio-occultation measurements. The novel identification algorithm analyses 2-week time slices between altitudes of 90–150 km, with Es layer events identified where the three selection criteria are met. Distinct seasonal distributions in Es occurrence were observed that are consistent with previous studies, with peaks during summer and reduced frequencies during winter, alignment of Es with geomagnetic contours, and layers descending in altitude as a function of local time. While discrepancies exist between WACCM-X and COSMIC data (WACCM-X occurrence rates are a factor of ∼2 lower than COSMIC-derived occurrence rates at mid-latitudes), highlighting the ongoing challenges in modeling Es layers, this study enhances the modeling capabilities of sporadic Es and deepens our understanding of their formation; it establishes a basis for their enhanced integration into global climate models and facilitates further investigation of Es behavior under different atmospheric conditions, paving the way to improved prediction of the occurrence of Es.</p>","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JA033044","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143110898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Constraints on the Observability of Energetic Neutral Atoms From the Magnetosphere-Atmosphere Interactions at Callisto and Europa","authors":"C. Michael Haynes,&nbsp;Tyler Tippens,&nbsp;Sven Simon,&nbsp;Lucas Liuzzo","doi":"10.1029/2024JA033391","DOIUrl":"https://doi.org/10.1029/2024JA033391","url":null,"abstract":"<p>We investigate the emission of energetic neutral atoms (ENAs) from the magnetosphere-atmosphere interactions at Europa and Callisto that may be observed by an ENA imaging instrument. To do so, we combine the draped electromagnetic fields from the AIKEF hybrid model with a tracing tool for the energetic magnetospheric parent ions. Using a realistic viewing geometry, synthetic ENA images are generated for multiple detector positions and orientations with respect to the magnetospheric field. At both moons, we investigate the ENA emission morphology at different distances to the center of Jupiter's plasma sheet. By generating ENA images for uniform electromagnetic fields as a baseline, we also constrain the influence of field line draping and induction signals on the observable ENA emission signatures. Our major findings are: (a) In uniform fields, regions of elevated ENA flux in the images populate segments of a ring around each moon's disc. (b) The radial and angular extensions of these segments decrease with growing magnetospheric field strength. (c) The angle between the detector's boresight vector and the ambient field determines the regions of the images populated with elevated ENA flux. (d) Non-uniformities in the fields are discernible in the ENA images only when Europa and Callisto are located near the center of Jupiter's plasma sheet. Even in this case, the visibility of such features is restricted to certain viewing geometries. (e) Anisotropies in the moons' atmospheric density profiles produce gradients in the observable ENA emissions. This facilitates a global characterization of these neutral envelopes through ENA imaging.</p>","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JA033391","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143121349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coupled Thermosphere-Ionosphere Tongue-Like Structure During the Recovery Phase of the Geomagnetic Storm on 12 May 2021","authors":"Tingting Yu,&nbsp;Zhipeng Ren,&nbsp;Biqiang Zhao,&nbsp;Nicholas Pedatella,&nbsp;Yong Wei,&nbsp;Shaoyang Li,&nbsp;Changzhi Zhai,&nbsp;Lingxin Zhao","doi":"10.1029/2024JA033119","DOIUrl":"https://doi.org/10.1029/2024JA033119","url":null,"abstract":"<p>A coupled thermosphere-ionosphere tongue-like structure was observed in the daytime at middle latitudes by ground-based Global Navigation Satellite System (GNSS) and Global-scale Observations of the Limb and Disk (GOLD) observations during the storm recovery phase on 12 May 2021. The storm-induced variations in total electron content (TEC) and the column density ratio of O to N₂ (∑O/N₂) both showed a relatively narrow region of enhancement in latitude, originating from low latitudes and surrounded by depleted regions. The concurrent neutral temperature observations also showed a tongue-like decrease surrounded by temperature enhancements. The Thermosphere-Ionosphere-Electrodynamics General Circulation Model (TIEGCM) qualitatively reproduced the observed thermosphere-ionosphere structure. The simulations indicate that the formation of the TEC tongue-like structure was dominated by the enhanced ΣO/N₂. Unlike the previously reported tongue of ionization (TOI) driven by E × B drifts, the tongue-like structure occurred at relatively lower geomagnetic latitudes (∼30<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>°</mo>\u0000 </mrow>\u0000 <annotation> $mathit{{}^{circ}}$</annotation>\u0000 </semantics></math>–∼65<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>°</mo>\u0000 </mrow>\u0000 <annotation> $mathit{{}^{circ}}$</annotation>\u0000 </semantics></math>) and had a smaller magnitude of enhancement. This is the first time that the concurrent tongue-like structures in thermospheric composition, temperature and electron density are observed, which advances the understanding of thermosphere-ionosphere coupling.</p>","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143121094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Geometrical Features of Magnetic Flux Entanglement Events Observed by MMS","authors":"Nisar Ahmad,&nbsp;Chao Shen,&nbsp;Yong Ji,&nbsp;Peng E,&nbsp;Umer Rehman,&nbsp;Guang-Rui Yao,&nbsp;Xiao-Jie Li,&nbsp;Ying-Jie Zhao,&nbsp;Yan-Fang Ji","doi":"10.1029/2024JA033305","DOIUrl":"https://doi.org/10.1029/2024JA033305","url":null,"abstract":"<p>Flux transfer events are momentary occurrences of self-adjusting, rope-like magnetized plasma structures near Earth's magnetopause, typically associated with a southward interplanetary magnetic field direction. This study aims to investigate the magnetic structural characteristics during three phases (initial, intermediate and final) of magnetic flux entanglement events and explore magnetic field gradient properties. Using the Nonlinear Magnetic Field Gradient Algorithm (NMG), we computed magnetic field curvature, helix angle, and torsion. Our analysis revealed that the central current sheet consistently exhibits the highest magnetic field curvature throughout all phases, while the lowest curvature occurs elsewhere. Notably, a polarity reversal in the normal component of magnetic field curvature is observed during the intermediate phase. The helix angle exhibits its maximum variation on both sides of the central current sheet during the initial phase. In the intermediate phase, however, the variation of the helix angle around the current sheet is minimal. By the final phase, the magnitude of the helix angle behaves in a manner opposite to that of the initial phase. Torsion around the current sheet initially undergoes significant changes during the initial phase but remains close to zero afterward. Conversely, in the intermediate phase, the magnetic flux regime shows minimal torsion initially, followed by an abrupt variations afterward. Nonetheless, during final phase, the magnetic flux regimes display a consistent pattern of increasing and decreasing torsion similar to the initial phase. In summary, flux tubes precede the emergence of flux ropes in the initial phase, structures resembling flux ropes dominate the intermediate phase, and both coexist in the final phase. This investigation sheds light on the interconnected nature of these structures, critical for understanding particle and energy exchange between the magnetosphere and solar wind.</p>","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143121095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the Relationship Between Traveling Atmospheric Disturbances and Traveling Ionospheric Disturbances","authors":"Bowei Liu,&nbsp;Jing Liu,&nbsp;Xuanqing Liu,&nbsp;Shuhan Li,&nbsp;Libo Liu","doi":"10.1029/2024JA033271","DOIUrl":"https://doi.org/10.1029/2024JA033271","url":null,"abstract":"<p>As the typical thermospheric/ionospheric wave, traveling atmospheric disturbances (TADs)/traveling ionospheric disturbances (TIDs) always carry and transfer a large amount of energy and momentum during geomagnetic storms. In this study, we conducted a model simulation to explore the relationship between TADs and TIDs. Our term analysis indicates that neutral wind transport plays an essential role in coupling TIDs with TADs. Meanwhile, ambipolar diffusion and photochemical processes act as dissipative mechanisms at relatively high and low altitudes, respectively. Further analysis along the tracks of TADs shows that the two manifestations of TIDs, the peak height and density of the F2 layer (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>h</mi>\u0000 <mi>m</mi>\u0000 </msub>\u0000 <msub>\u0000 <mi>F</mi>\u0000 <mn>2</mn>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${h}_{mathrm{m}}{F}_{2}$</annotation>\u0000 </semantics></math> and <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>N</mi>\u0000 <mi>m</mi>\u0000 </msub>\u0000 <msub>\u0000 <mi>F</mi>\u0000 <mn>2</mn>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${N}_{mathrm{m}}{F}_{2}$</annotation>\u0000 </semantics></math>) perturbations, are anti-correlated. This anticorrelation is driven by neutral wind transport caused by plasma density gradients near <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>h</mi>\u0000 <mi>m</mi>\u0000 </msub>\u0000 <msub>\u0000 <mi>F</mi>\u0000 <mn>2</mn>\u0000 </msub>\u0000 </mrow>\u0000 <annotation> ${h}_{mathrm{m}}{F}_{2}$</annotation>\u0000 </semantics></math>. When TIDs manifest as Total Electron Content (TEC) perturbations, neutral wind perturbations (TADs) modulate TIDs through photochemical processes by raising and lowering the ionosphere. Finally, we discuss how TADs modulate TIDs at different altitudes, latitudes, and hemispheres. We demonstrate that the hemispheric asymmetry of the O/N₂ ratio leads to a corresponding hemispheric asymmetry in TIDs. Our findings enhance the understanding of how the thermosphere and ionosphere are coupled through waves and how energy and momentum are exchanged in the thermosphere-ionosphere system via these waves.</p>","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143121093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Total Ionizing Dose Measured With the Radiation Dosimeter Onboard the FY-3E Satellite","authors":"B. Q. Zhang,&nbsp;G. H. Shen,&nbsp;C. Huang,&nbsp;Y. Sun,&nbsp;Y. Chang,&nbsp;J. T. Lü,&nbsp;P. F. Zhang,&nbsp;C. Q. Wang,&nbsp;Z. Chang,&nbsp;X. G. Zhang","doi":"10.1029/2024JA033016","DOIUrl":"https://doi.org/10.1029/2024JA033016","url":null,"abstract":"<p>FengYun-3E (FY-3E) was the first operational meteorological satellite in China in early morning orbit. The radiation dosimeter, which is part of the satellite's Space Environment Monitor (SEM), contains three probes to measure the total ionizing dose in the three directions of the satellite. Improvements in the dosimeter have been made to increase detection sensitivity. The RADFET, a radiation dose sensor, was calibrated using ⁶⁰Co radionuclide source to correlate its threshold voltage shift with the total ionizing dose. The improved dosimeter has a sensitivity of 0.06 rad (Si) to 0.45 rad (Si) in the measurement range. The flight data showed that the total ionizing dose within the FY-3E satellite is anisotropic. The radiation dose rate in the +X and +Y directions increased by a few factors after the geomagnetic storms.</p>","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143120433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}